How can i upgrade to appium 1.6.1-beta

Hi,
Im trying to upgrade my appium version to 1.6.1beta on mac El Capitan 10.11.6
by run : sudo npm install -g [email protected] and it returns error:

npm WARN deprecated [email protected]: Babel 5 is no longer being maintained. Upgrade to Babel 6.
npm WARN deprecated [email protected]: Please update to minimatch 3.0.2 or higher to avoid a RegExp DoS issue
npm WARN deprecated [email protected]: Copy its ~20 LOC directly into your code instead.
/usr/local/lib
└── (empty)

npm ERR! Darwin 15.6.0
npm ERR! argv “/usr/local/Cellar/node/5.10.1/bin/node” “/usr/local/bin/npm” “install” “-g” “[email protected]
npm ERR! node v5.10.1
npm ERR! npm v3.8.3
npm ERR! path /usr/local/bin/appium
npm ERR! code EEXIST

npm ERR! Refusing to delete /usr/local/bin/appium: …/lib/node_modules/appium/bin/appium.js symlink target is not controlled by npm /usr/local
npm ERR! File exists: /usr/local/bin/appium
npm ERR! Move it away, and try again.

npm ERR! Please include the following file with any support request:
npm ERR! /Users/automation/npm-debug.log
npm ERR! code 1

and i also need to upgrade my client version.
help me please .

npm uninstall -g appium
npm install -g [email protected]

@Aleksei: i already uninstalled appium and got the same error.
Anyway i found the problem:
after uninstall, appium folder remains under: usr/local/bin.
i deleted the folder and upgrade node version to 7.0.0 and installation succeeded